The long-term objective of this work is the development and application of synthetic methods for the preparation of structurally diversified amino acid derivatives. The utilization of natural and unnatural alpha-amino acids in practically all areas of the physical and life sciences continues to grow at an impressive rate. In addition to their key biological role as the "building blocks" of peptides, proteins and other natural products, the alpha-amino acids are used extensively in the pharmaceutical, agrochemical and food industries. They have also been utilized in total synthesis and other synthetic studies, both as sources of chirality in final products and as chiral auxiliaries, reagents, and catalysts for asymmetric synthesis. Because of this widespread use, new and versatile methods for both the small and large scale preparation of natural as well as structurally diversified alpha-amino acid derivatives are important. Methods for the asymmetric synthesis of alpha-amino acids, especially those which involve catalytic enantiocontrol, are of special practical interest. Synthetic studies will be pursued using two complimentary systems: anionic and cationic amino acid equivalents. The first practical asymmetric synthesis of amino acids using phase transfer catalysis has been reported from the anionic equivalent of the simplest amino acid, glycine. The applications of this technique will be expanded and in-depth studies probing the mechanism of this important reaction will be conducted. A complimentary catalytic asymmetric synthesis of amino acids from cationic derivatives is also being developed by utilizing the unique chemical properties of our substrates. A number of natural and/or rare amino acids are targets for our synthetic studies. Their syntheses will demonstrate both the scope and potential of the chemistry we are studying.